THE main sticking point between the Senate and House versions of the aviation security bill now headed for conference is whether airport magnetometers will be run by private firms or the smooth efficiency of the Department of Motor Vehicles. Only liberals still associate the words "government employee" with "efficiency" and "competence."

This is lesson No. 1,475,607,033 on the point that the free market is a counterintuitive concept. Without constant reminders of the material bounty produced by the glorious Soviet Union, people, by which I mean "liberals," will list toward socialist solutions time and again.

Even the lily-livered Europeans, usually cited warmly by the left for their progressive views on adultery, have abandoned the idea of government bureaucrats running security at airports. But The New York Times has been editorializing daily against private security firms in deference to -- and I quote -- "a highly trained federal force." The only rhetorical flourish the Times avoided was to call the private sector workers "shiftless."

Far be it for me to defend airport security personnel, but making them government employees, I assure you, will not improve matters. We're not going to call out the Marines to rifle through little old ladies' handbags before they board flights to Cleveland. This is HillaryCare for the airports.

The reason airports already resemble the torture chambers in Orwell's "1984" is that they are natural monopolies. If you live in Chicago, you can't decide you really prefer the Dallas airport and will fly only out of Dallas henceforth. You're stuck in Chicago, and O'Hare knows you're stuck with Chicago airports. (There is no other explanation for why there even is an airport in Chicago. Planes are only allowed to fly in or out of O'Hare for approximately 20 minutes every week.)

The absence of competition among airports leads to phenomenally stupid inconveniences unfathomable in a competitive environment.

Only a monopoly would ban the world's most popular soft drink (Coke) from being sold on its premises. Only a monopoly would have bathrooms that still employ those ridiculous Potemkin hand dryers in lieu of something that might possibly dry your hands, like paper towels. Only a monopoly could force people to stand in two-hour lines in order to answer stupid questions.

What are you going to do? Leave from the Honolulu airport on your next trip?

The liberal's solution to a monopoly is invariably to create an even bigger monopoly by turning it over to the government. Not surprisingly, the only experiences nearly as unpleasant as commercial air travel are those run exclusively by the government -- the biggest monopoly of all. If you had to get up tomorrow morning and get a passport, a driver's license or a lamp, which would you dread most?

At least partial monopolies lead only to airports. Total monopolies lead to the Khmer Rouge.

The only effective solution to a natural monopoly is for the government to create artificial competition by setting standards (off the top of my head, for example -- no box cutters on airplanes) and fining airports that fail random spot checks. Even for trivial safety matters like underage drinking or cigarette smoking in Los Angeles bars, the government doesn't impose a government workforce to tend bar. It fines bars that fail to comply with the law.

Moreover, I wish the security guards luck, but keeping weapons off planes is not the linchpin to safe skies anyway. It better not be: We can't keep weapons out of prisons; we certainly can't keep them off airplanes. Unless the airlines are going to require all passengers, pilots and crew to fly naked with no carry-on luggage, keeping weapons off planes is a pipe dream.

The airport shakedowns do, however, comply with the government's primary criterion for airport safety, which is that all travelers be inconvenienced with absolutely no concomitant benefit.

Thus, one of the FAA's recent safety innovations is to demand photo IDs from passengers at various checkpoints throughout the terminal. For maximum annoyance, this includes the moment at which you are just about to enter the gangplank to board the plane, carrying luggage, newspapers, a beverage, and holding your boarding pass between your teeth.

But we all have to make sacrifices, and studies have shown that demanding photo ID is a highly effective method of keeping vampires off airplanes. The defect in the photo ID requirement is that terrorists, unlike vampires, are capable of having their photos taken.

No one has told the FAA this -- but terrorists have ID cards. Instruction No. 12 of the terrorists' pre-attack manual was to "bless ... your ID, your passport and all of your papers." (But the classic hijacker instructions regarded cleanliness. Instruction No. 1 was to put on cologne. Instruction No. 2 was to shower. See -- it doesn't work if you put on cologne and then shower ...)
If the government demanded results -- say, no bombs on airplanes -- airports wouldn't have time to engage in man's truly oldest profession, oppressing his fellow man. Instead, this natural monopoly would finally be forced to stop harassing passengers for the fun of it and to adopt safety procedures that would have the novel attribute of making planes
safe.